Hello,
Thanks for posting your query.
Terbenafine has not been reported to be associated with a decreased sperm count or motility in the literature. The findings of decreased count and motility of the sperms is not likely to be due to the treatment you are taking with the anti fungal agent.
You can safely complete your treatment for fungal infection and then attend an infertility clinic for further management.
Hope this answers your query. I will be glad to answer the follow up queries that you have.
Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.

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